Diaphragm valves



Aug. 9, 1960 N. MERRILL DIAPHRAGM VALVES 3 Sheets-Sheet 1 Filed Nov. 29,1955 FIG. [.f

INVENTOR N NUTTALL MERRILL ATTORNEY.

Allg' 9, 1960 l. N. MERRILL 2,948,504

DIAPHRAGM VALVES Filed Nov. 29, 1955 5 Sheets-Sheet 3 n ventor ByqwwHarney l centre. y 'slightly less than the inside surface area of theflexible United States Patent A DIAPHRAGM VALVES Ian Nuttall Merrill,Clarendon House, Brnclite,

Sheffield, England Filed Nov. 29, 1955, Ser. N 0. 549,812

1 Claim. (Cl. 251-258) The present invention concerns diaphragm valvesfor controlling and effecting, respectively, the ow liquids, and/ orsolids, in pipe lines.

One object of the present invention is to provide a valve having adiaphragm of simple and robust shape which in operation is substantiallyfree from'stretching and straining and which avoids the use ofmechanical attachments such as Would cause local stresses.

Anothersobject of the present invention is to reduce the wear on thecontactingy parts of a diaphragm valve and to ensure that the closureforce has a predetermined fixed limit which prevents the possibility ofdamage due to application of excessivemanual pressure.

Furtherobjects Vinclude the provision of a valve the body of which is ofsimple shape and smooth contours suitable for being lined with resistantmaterial such as rubber, lead, glass, or plastics; -to avoid pocketswhich might collect liquids or solids and to permit of easy draining,flushing and sterilizing; and to enable a substantially unrestricted andstreamline ow to obtain through the valve with extremely low pressuredrop across it.

According to the present invention the displaceable member of adiaphragm valve includes at least one ilexible tube, non-rotatablymounted and deformable for valve operation by a rotary cam (hereinaftercalled a rotor) disposed within it.

In a diaphragm valve the closure member constituted by `a flexible tubeis preferably secured in both end regions against rotation relative tovthe valve body, but presents an intermediate free region deformable bythe rotor into appropriate shapes for open and closed positions of thevalve.

The body of the valve preferablI has an approximately spherical shapewith smooth contours towards the inlet and outlet connections, which maybe in the form of anges or conventional valve and pipe line connections,e.g. conical anges', spigot and socket, screwing, etc. Diametricallyopposite openings across the axis of the valve body between the endconnections, provide location for a substantial tubular diaphragm ofilexible material, such as natural or synthetic rubber. For instancechemical rubber, butyl rubber, neoprene rubber, hypalon, or othersuitable material. Polyvinyl chloride may be used. Metal sleeves pressedinside the open ends of the flexible tube, by interference arepreferably used to seal the tub into the valve body.

The rotor which is preferably of a shape having diametrically oppositetapering lobes, is located inside the free central section of theflexible tube and is turned by a spindle or shaft located in the bushedmetal sleeves which x the tube diaphragm ends. The rotor, whichpreferably works in a bath of suitable lubricant, such as castor basehydraulic iluid, has cylindrical ends and tapers towards an oval ordouble lobe section at the It is made to have a superiicial peripheralarea of gases,

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tube in which it turns, and which it consequently fully supports. Whenthe rotor is turned the iiexible tube in effect flows over it, changingcontour with rthe surface of the rotor as it does so.

Turning the lobe section of the rotor into` a vertical position has theeffect of pushing the material of the llexible tube against thetransverse periphery of the inside of the valve body to an extentdetermined by the dimensions of the body at this point. This closes thevalve and stops flow in a manner calculated to Vgive the minimum wear,'the ilexible material of the tube beingliterally rolled into cushionedcontact with the valve body. Conversely, turning the lobe section of therotor into a horizontal plane has the elect of moving the flexible tubeaway from the top and bottom of the valve body, and allowing streamlinedflow above and below the ilattened tube. With these' andother objects inview which will become apparent in the following detailed description,the'present invention will be clearly understood in connection with theaccompanying drawings, in which:

- Figure l is a side elevation of a valve bodly; l

Fig. la-is a side elevation of an alternativeform of a valve body; y i Yi Fig. 2 is a section along the lines 2 2 of'Fig. l;

Fig. 2a is a section similar to that shown in Fig. 2, yet the diaphragmVclosure member being in a dilerent position;

-Fig. 3 is a section along the lines 3%3 of Fig. 2;v

Fig. 3a isa section along the lines 3a--3a of Fig. 2a. Fig. 4 is `alongitudinal section, partly in elevation showing another form of valveconstruction in accordance with the invention;

Fig. 5 is a section on the line V-V of Fig. 4; and Fig. 6 is a view insection similar to that of Fig. 5 showing the structure of a multi-waydiaphragm valve.

Referring now to the drawings, and in particular to Figs. l, la and 3,3a, a valve body B may be made in one piece (Fig. la) or may be of splitconstruction bolted together (Figs. l, 3 and 3a). In either case itcomprises a generally spherical central portion 11 with flanged inletand outlet connections 12 and 13, rpectively.

The split type of body enables a renewable valve seating ring S to bemoulded in a dovetail section groove 14.

The diaphragm closure member D is constituted by a exible tube, and hasits opposite ends anchored in coaxial bores 15 and 16 in the body byangedinterference metal sleeves F1 and F2. Each of the bores 15 and 16has two cannelures or circumferentially extending grooves into which thematerial of the diaphragm is expanded for the better sealing effect.

A rotor R has an operating spindle 21 terminating in a square head 22and journalled in a bushing 23 inthe flanged sleeve F1 and a smallerbearing spindle 25 journalled in a bushing 26 in the anged sleeve F2.

Where the body is of unitary construction the rotor must necessarily bebuilt up from more than one piece, in order to assemble the valve.

Instead of using flanged metal sleeves the diaphragm may be formed withintegrally moulded anged end portions.

In the valve of Figs. 4 and 5 the rotor R is olfset from the axis of theinlet and outlet connections 12, 13 of the body B. closure member Doccurs in the closed condition of the rotor, with respect to an inletport 22 on the side of the inlet connection, and with respect to anoutlet port 24 on the outlet side.

The rotor R is rotatably mounted in fittings F3 and F4 which are locatedwithin the body B by a washer W and In this case a double seating of thediaphragm v 3 an end plate P, respectively,` bearing on spring circlipsC1 and C2.

Obviously with such a construction, by providing a connection to thecentral portion of the body a two-way diaphragm valve can be made.Similarly multi-way'valve constructions are possible by providing morethan two seatings.

In the valve shown in Fig. 6th@ rotor R can position the diaphragm D asshown in fullk lines whereby no communication obtains between any of thefour connections 31, 32, 33 and 34. In an intermediate position of therotor the diaphragm is disposed as indicated in chaindotted lines, thusproviding communication between connections31 and 34 and betweenconnections 32' and 33. In a diaphragm position at right angles to thatshown in chain-dotted lines communication obtains between connections 31and 32 and between connections 33 and 34. Thus a double-two-way ormulti-way valve is provided.

While I have disclosed several embodiments of the present invention, itis to be understood that these embodiments are given by example only andnot in a limiting sense, the scope of the presentinvention beingdetermined by the objects and the claim.

I claim:

A diaphragm valve comprising a valve body, having inlet and outletapertures with a ow passage therebetween, said valve body havingdiarnetrically opposite bores transverse to the longitudinal axis ofsaid flow passage, a closure member, metal sleeves, spring washers and arotor, said inlet and outlet apertures being on opposite sides of saidvalve body, and said closure member comprising, a flexible tube ofsubstantially uniform crosssectional area throughout its length and saiddiametrically vopposed bores having circumferentially extending grooves,

said metal sleeves being pressed into the ends of said flexible tube tohold said exible tube against rotation relative to said valve body sothat said flexible tube expands into said circumferentially extendinggrooves, said spring washers being fitted into said bores to retain saidmetal sleeves with said valve body, said rotor having bearing means insaid metal sleeves and being encased by said flexible tube, and saidrotor having cylindrical ends sloping towards a lobe sectionl near themid-region thereof deforming an intermediate portion lof said :exibletube, said lobe section being eccentric relative to said cylindricalends,y rotation of said rotor relative to said valve body and said'flexible tube causing said flexible tube to be moved into or out of theflow passage through said valve, and said rotor working within an oilbath within said eXible sleeve.

References Cited in the le of this patentv I UNITED STATES PATENTS2,381,544 Jacobsen Aug. 7, 1945 2,397,373 Saunders 1 Mar. 26, 19462,519,642 Ford Aug'. 22, 1950 2,534,577 Courtot Dec. 19, 1950 2,583,572Huber Ian. 29, 195-2 2,620,815 Margraf Dec. 9, 1952 2,784,934 PauliusMar. 1'2, 1957 2,812,154 Nordstrand Nov. 5, 1957 FOREIGN PATENTS 623,696Great Britain May 20, 1949 1,023,320 France of. 1952 143,999 Sweden: of1954

